Variable pitch and reversible propeller



June 3, 1930.

B. J. STEINMETZ VARIABLE PITCH AND REVERSIBLE PROPELLER Filed Sept. 14,1927 2 Sheets-Sheet. 1

IN V EN TOR.

A TTORNEY I June 3, 1930. Y B. J. STEINMETZ ,6

VARIABLE PITCH AND REVERSIBLE PRoPELL R Filed Sept. 14, 1927 2Sheets-Sheet. 2

INVENTOR,

EM 6.5mm

v able that some feature ofspeed control he longitudinal axes PatentedJune 3, 1930 Bml-TLMIN J. STEINHETZ OF YORK, N. Y.

VARIABLE PITCH AND REVERSIBLE PROPELLER Application filed September 14',1927. Serial No. 219,453.

This invention relates to aeroplanes and like aerial machin'es,whetherof the heavierthan-air, self-buoyant, or other types depending foradvancement upon the rotation 5 of bladed propellers, and the inventionresides more particularly in the mounting and control of such propellerblades.

Notwithstanding the great amount of thought and experimentation that isbestowed on the subject bf aerial navigation, no particular advancementhas been made in the propellers, designers having contented themselveswith copying the earlier rigid models, making improvements only in shapeand in the selection of material, all being rigidly fixed in a revolublehead, the same being in effect a hub carried on the forward end 'of amotor driven shaft disposed longitudinally of the machine.

It is, however, regarded as highly desirw rovided for advancement of themachine through the air,irrespective of the rate of revolution of the-motor,- for it is known that such motors are variable in speed, asduring intervals of racing and also that slowin of the motor isaccomplished by throtthng orcutting off of the impulsive medium, thusreducing the generation of energy.

Havin this subject in mind,it' is the main object o the presentinvention to provide means for increasing or decreasing the pitch of thepropeller blades whereby their propulsive force may be measurablymodified withoutrecourse to changing the speed of p the motor. v Afurther feature is in the provision of means whereby the propellerblades will automatically assume an angle -or pitch adapted to cause anincreased forward movement of the machine, such arrangement being highlydesirable when the machine reaches a high altitude or enters a thin orattenuated stratum of air in which the usual pitch of the blades isinsufiicient to properly propel the machine.

Another purpose is to produce propeller blades so mounted to any desiredextent 1 as at 16, and terminates in a further reduced 0 as to turn upontheir either controlled by an operator, or automatlcally as may bepreferred, and which can be completely reversed to act as a brake inretarding the machine, as at landing or approaching a mooring mast.

These and other like objects, which will become apparent as thedescription pro-' gresses, are accomplished by the novel constructionand arrangement of parts hereinafter described and illustrated in theaccompanymg drawings, forming a material part of this disclosure, and inwhich 4 Figure 1 is a top plan view of an aeroplane nose as made inaccordance with the invention, the casing being in section to show theinterior.

Flgure 2 is a transverse sectional view of the same, the casing beingpartially in end elevation, the section being taken on line 2-2 ofFigure 3.

Figure 3 is a partial longitudinal sectional v1 ew-, taken in a plane ata right angle to Figure 1,'and drawn to an enlarged scale.

F gure 4 is a partial end and transverse sectlonalview, similar toFigure 2, but showing a modified form' of manually operated control. 1

Throughout the several views the numeral 10 designates a motor drivenshaft extend- 1ng outwardly at the front of the fuselage of a flyingmachine of whatever type may be used.

Tight fitted and keyed to the projecting ortion of the shaft is a sleevell reaching integrally outward from the. rear wall'12 of a shortcylindrical casing 14 disposed closely adjacent the front end wall ofthe fuselage, and removably attached to the open front end of the casingis a hollow conical nose 15, the attachment being made by screws or likefastenings as shown.

In the preferred form, shown in Figures 1, 2 and 3, the outer portion ofthe shaft is shouldered, reduced and screw threaded,

the same being engaged threaded step 17 hub 18 of the conical in aninreachmg nose 15.

A circular plate 19 is bored to fit over the threaded portion 16of theshaft to be firmly mo held against its shoulder by a clamp nut 20, and.extending from the periphery of the plate are several airs of lugs 21.

The plate 19 a 0 makes contact wlth the end of the sleeve 11, whichextends coincident with the extending portion of the shaft 10, and a key22 in the plate engages a slot in the sleeve end so that the severalparts rotate as a unit.

Pivoted between each of the paired lugs 21 are links 23, their oppositeends being re duced in thickness and connected with the similarlyreduced ends of another set of links 24, the connections being made inthe slotted bodies of weights 25, by pins 26, the arrangement being ofthe well known centrifugal governor type.

The opposite, rearwardly extending ends of the links 24 are ivotallyconnected between lugs 27 reaching radially outward from an annulus 29slidable on the sleeve 11, to which t is keyed to prevent relativerotation, and carried by the annulus is a spur toothed rack 30.

A coiled expansion spring 31, here shown of rectangular cross section,encircles the sleeve 11, its ends abutting the plate 19 and annulus29respectively, thus normally pressing the rack carrying annulusrearwardly, but yielding under the centrifugal force exerted through thelinks by the weights when the device is rapidly rotated.

' Meshed with the rack 30 is a pinion 32 fixed on'a shaft 33, rotatablymounted in bearings 34 secured on the casing plate 12 and extendingequally in both directions, at

g a right angle to and above the, drive shaft 10.

Fixed on the ends of the shaft 33 are bevel gears 35 to mesh with matinggears 36 rigid with worms 37 having pintles rotatable in bearings 38secured in opposite sides of the casin 14. As shown, the'shaft 33 isdispose in an offset plane parallel to the blade axes and to preventundesirable vibration that would result from such construction, it isunderstood that a suitable counterbalance of weight equalling that ofsaid shaft and disposed a distance equal to that of the shaft and on theopposite side of said plane, is to be provided in the finished device.

The propeller blades used in connection with this invention are providedwith cylindrical hubs 40 at their inner ends, having reduced bearingportions 41 housed in outwardly extending housings 42 integral with thecasing 14 and arranged in diametrically opposite relation.

The inner extending ends of the blades carry worm wheels 43, heldrigidly by keys and clamp nuts 44, to be engaged by the worms 37, thearrangement bemg such that the. propeller blades are firmly held intheir bearm s and prevented from endwise movement, but permitted topartially rotate on their longitudinal axis at such time and to shaft,an acutely rotatably journalled therein 'the extent of the governorcontrol action, returning to their' original position when,- ever anexcess speed is reduced to normal.

In the modification shown in Figure 4 the ball or centrifugal governoris dispensed with and the shaft 33 actuated by another method under theimmediate control of an operator. Y

This method consists of the use of one or more small electric motors 50,suitably mounted in the casing 14, their shafts 51 having fixed worms 52meshing with worm wheels 53 fixed on the shaft 33.

These motors are adapted to run in either direction, under control of anoperator; as is also the duration orti me period of their rotation.

The foregoing disclosure is to be regarded as descriptive andillustrative only, and not as restrictive or limitative of theinvention, of which obviously an embodiment may be constructed includingmany modifications without departing from the general scope hereinindicated and denoted in the appended claims. I

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is

1. A flying machine having a propeller pointed conical casing on theextendin end thereof, opposed radial propeller bla es journalled torotate in said casing, worm wheels fixed directly on the inner ends ofsaid blades, train gears operatively engaging the wormwheels, acentrifugal governor in said casin and rack and plnion means controlledby t e action of said governor to actuate said train gears.

2. A flying machine having a shaft, a casing on the extending en asleeve on said casing fixed on the shaft, a collar keyed to slide onsaid sleeve, a spring encircling the sleeve to press said collarrearwardly against a stop, a centrifugal governor in said casing to movesaid sleeve against the action of said spring upon attaining anabnormally high speed, a pair of propeller blades journalled in saidcasing, a transverse shaft gearedto the inner ends of said blades, andpositive means actuated by the movement of said collar to transmitrotary motion to said transverse shaft.

fpropeller thereof,

3. A flying machine having diametrically opposed variable pitchpropellers, worm wheels fixed to the inner ends of the propellers,positive worm and gear connections to modify the pitch of said bladeswhile the machine is in motion, a single rotatable shaft to operate saidconnections, and means to rotate said shaft in either direction.

4. In an aerial machine, the combination with a frame-having radialpropeller blades to rotate on longitudinalaxes, of a single shaft diosed in an offset plane parallel to the bla e axes,

worm and gear connections between the outer ends of said shaft andtheinner ends of said blades to cause semi-rotation of said blades Y ontheir axes, and controllable means to actuate said shaft, said meansbeing mechanically operated within said frame. A 5. In a flying'machinehaving a propeller shaft, :1. drive head having a conical point fixedthereon, propeller blades extending m dially from sald head, said bladesbeing rotatable on their longitudinal axes, means wholl contained insaid head for rotating said lades on their longitudinal axes to changethe pitch thereof, said means comprising a sleeve slidable on thepropeller shaft, a rack carried by said sleeve, a centrifugal governorto actuate said sleeve, a shaft having a pinion meshed with said rack,and positive geared connections between said shaft and'the inner ends ofsaid propeller blades to cause rotation of the same when the machine isin motion.

In testimon whereof I aflix m signature. BElUAMIN J. STE ETZ.-

